Machine for grinding coiled springs.



F. H. HALSTEAD.

MACHINE FOR GRINDING COILED SPRINGS.

. APPLICATION FILED MAY II, 1914. I 1,142,700. Patentedllune 8,1915;

4 SHEETSSHEET 1.

F. H. HALSTEAD. MACHINE FOR GRINDING COILED SPRINGS.

APPLICATION FILED MAY ll, 1'9I4- 1,142,?0, Patented June 8, 1915.

:1 SHEETS-SHEET 2.

F. H. HALSTEAD.

MACHINE FOR GRINDING COILED SPRINGS.

APPLICATION FILED MAY II, 1914. 1 143,700, PatentedJune 8, 1915.

4 SHEETSSHEET 3- MQW P Attorneys.

F. H. HALSTEAD.

MACHINE FOR GRINDING COILED SPRINGS.

APPLICATION FILED MAY II, I9I4.

.PareutedJune 8; 1915.

4 SHEETS-SHEET 4.

UNITED STATES PATENT OFFICE.

FREDERICK nfnnnsrnnn, F WORCESTER, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGNMENTS, TO HALSTEAD ,MACHINE COMPANY, A CORPORATION OF 'MASSA- CHUSETTS.

Specification of Letters Patent.

MACHINE FOR GRINDING- COILED SPRINGS.

Patented June 8, 1915.

- I Application filed May 11, 1914. Serial No. 837,688.

To all whom it may concern STE'AD, a citizen of the United States, residing at Worcester, in the county of Worcester and State of Massachusetts, have invented a new and useful Machine for Grinding Coiled Springs, of which the following is aspecification.

This invention relates to a machine for grinding coiled springs.

The grinding of these springs presents certain problems which are not found ordinarily in grinding processes. It is not desired to grind springs exactly to a definite length, because as manufactured they cannot be made of the same length and it is not necessary that they should be. They are made approximately to length and each end of the coil is brought into contact with the next wire so as to make a portion of a coil in a plane substantially at right-angles to the axis of the spring. It is desired to square off these ends without any danger of griniing more than about a third of the Way through the wire and leaving the springs otherwise of substantially their original length. Owing to this fact it has been the custom, so far as I am aware, to,

grind these" springs by hand.

The principal objects of this invention are .to provide a machine which will simultaneously grind both ends of-the springs'without grinding the long springs any more than it does the short ones and leaving the springs in their original relative lengths with both ends ground square; also to provide a mechanism by which the. springs may be presented to the grinding wheels in such. a way as to accomplish this result; improved means for feeding the springs to and from the .wheels, and especially to provide for holdlng the springs in such a way that the proper grinding operation will take place:

The invention also involves other features of the machine and the method involved.

Reference is to be had to the accompanying drawings in which,

Figure l is a plan of a spring grinding machine constructed in accordance with this invention; Fig. 2 is a longitudinal sectional view on a line just at the left of the righthand grinding wheel in Fig. 1. Fig. 3 is an.

end elevation showing some parts in section Fig. 4 isa plan of the feeding device, and

a belt contacting with two pullevs 15 and an idler 15 Each of the pulleys 15 is on a shaft 16. Un each of these shafts are two 0 long-faced pulleys 17. Each of these pulleys drives a pulley 18 on a shaft 19, which carries a grinding wheel 20. It will be seen.

therefore, that in the form shown, four of these grinding wheels are illustrated, two

for roughing and two for finishing, but any other even number can be used according to this invention.

The shafts 19 arecarried in bearings'21 mounted on slides 22, and these slides are adapted to be adjusted by screws 23 sup ported in hubs 24" on the frame. The object of the long-faced pulleys 17 will be obvious,

therefore. These grinding wheels are arranged in bearings inside a guard 25 and adapted to grind the ends of the springs, as will appear herein.

by a driving pulley 31 which, by'means of gearing 32, drives a. transverse shaft 33.

This shaft is provided with a polygonal drum 34 and at the other end of the machine is a similar shaft 33 having a duplicate drum 35 thereon. These drums are provided for the purpose of supporting and operating an endless chain conveyer comprisinga series of-main links 36 pivoted together and each having a length between pivots equivalent to the length of oneof the sides of each of the polygonal drum.

The frame has guides 29 for the links of the endless chain conveyer.

Each of the links composing this chain is provided with two jaws thereon designated 37 and 38, respectively. The front jaw 3"? is fixed to its link bv a pin 39 extending through the jaw near the base thereof and entering anopen ended slot 40 in the front of the link. The base of this jaw fits down against the end of aspring 41 which is held at that end against the link and operates with a constant pressure against the front side of the rear jaw 38. This jaw is pivoted to the link on a shaft 42. The swinging of On the machlne 18 another shaft 30 driven swings in either direction.

springs are carried by the chain.

the jaw 38 about its pivot is limited by two surfaces 43 at the bottom which come into contact with the top of the link as'the jaw The jaw 37 is made with a V-shaped surface for engaging the springs and the jaw 38 with a convex surface opposite the angle of the V. In this way the springs are engaged by three surfaces.

Each jaw 37 is provided with a forwardly projecting horn or rest 44 for supporting the springs when first fed to the jaws and preventing their dislodgment from between them. Each jaw 37 is also provided with 'a rearwardly extending guard plate 45, c0 operating with the hopper which will now be described.

The frame of the machine is provided with a pair of projections 46 located on opposite sides of the conveyer and each of these is provided with ways in whichmoves a slide 47. A screw 48 is employed for adjusting said slide back and forth. The end of each of these slides is provided with a longitudinal member 49 which constitutes one side of the pathway through which the These sides 49 can be adjusted toward and from each other by the'screws 48. They are provided on their inner sides, with guides 50 which converge from the position in which the springs are introduced to a position forward thereof-from which they are carried by the chain. The purpose of this will appear presently.

The projections 46 also support the sides 51 which, together with the ends 52 and 53, constitute the hopper for feeding the springs. The end 52 is fixed on the side members but the end 53 is made adjustable by meansof side fianges54 having longitudinal slots '55 through which screws 56 are secured. By means of this adjustment,

the hopper can be made to have a proper sized passage at the bottom for permitting springs of different sizes to be discharged into the feed chain.

The operation of this part of the device is as fol oWs: The coiled springs are placed horizontally in the hopper. The bottom one will rest on the plate 45 as the chain-travels until the chain reaches the position shown in Fig. 5. Then this bottom spring will feed down by gravity and rest on the horn 44. Then as the chain-travels next spring and the spring that has been fed down-will be forwarded. Three positions of such a s'prin are shown in Fig. 5. As the chain trave s u the ascending side of the drum, the jaw 3 gradually closes while the jaw 38 is held in its rearmost position -by the spring 41. When the link finally comes to horizontal position, the jaw 37 is along the -top,- the following jaw 37 will close the bottom of the hopper against the passage of the forced over against the jaw 38 and in fact forces the latter jaw to swing on its pivot against the resistance of the spring 41 to its limiting position and in that position the spring being fed along is clamped between the two jaws. During this motion it will be seen that while the spring is loose between the jaws and is being carried forward, it passes between the converging edges of the guides 50 and, if longer than the shortest distance between them, is gradually forced into a contracted position so that all the springs, independently of their varying lengths, are finally brought to a uniform length before they are gripped firmly between the jaws. When they are so gripped they are held at that length by the aws and then carried on between the grinding wheels and ground with their ends at a uniform distance apart. The guides 29 accurately hold the chain and also the springs wheels. As the links an jaws separate uponpassing over the drum 34 at the discharge end of the machine the springs are released so that they expand to their original lengths. They are supported on the projections or horns 44 and in contact with the forward jaws 38. Tnorder to discharge the springs all at the samepoint a pair of rods 59 are provided. These are fixed to a stationary part of the machine and project downwardly at an inclination at opposite sides of the chain so that they do not touch the chain. They are so located thatwhen the springs are brought around to them the ends of the springs, which at this time project beyond the sides of the jaws, will engage these rods and be prevented from passing beyond them with the chain. The springs must necessarily slide or roll down along these rods and drop off their ends when they can be caught in a suitable receptacle or on a conveyer or the like. Springs of uniform length can also be ground on this machine.

From what has been stated it will be seen that by this method springs of varying lengths can be first brought by compression to a uniform longitudinal dimension 'and held fby the jaws in that position with the "end coils of the springs projecting beyond ends of the jaws and they are released from the conveyer in an extremely simple manner. By using the guides 50 simply as guides the machine can be used for grinding solid articles also.

, Although I have illustrated and described only a single embodiment of the invention, I am aware of the fact that many modifications can be made therein by any person i feeding the springs, of means for compressing said springs to bring their lengths to a .uniform dimension and grinding meansin position to grind the ends of said springs while they are under compression.

2. In a machine for grinding coiled springs, the combination of means for compressing the springs longitudinally to bring their lengths to a uniform dimension and a pair of grinding wheels located opposite each other in position to grind the ends of said springs while they are under compres- S1011.

3. In a machine for grinding coiled springs, the combination with means for feeding a series of said springs forward laterally, a guide located at the sides of said feeding means, said guide having surfaces in a position to engage the ends of said springs as'they are fed forward, said surfaces gradually converging, whereby said springs are compressed to a uniform length, means for gripping said springs while in said compressed condition, and holding them in that condition while being fed forward, and a pair of grinding devices at a predetermined distance apart in position to grind the opposite ends of said springs while held by said jaws in compressed condition.

4. In a machine for grinding coiled springs, the combination with means for feeding said springs forward laterally, means located at the sides of said feeding means for compressing said springs to a uniform length, said feeding means having jaws constructed and arranged to grip said springs while in said compressed condition, hold them in that condition, and feed them forward, a pair of grinding wheels at a predetermined distance apart in position to grind the opposite ends of said springs while held by-said jaws in compressed condition, said feeding means being arranged to feed the springs forward constantly during the grinding operation, and means whereby said springs are released by the jaws and allowed to resume their normal lengths and are then carried forward by the jaws and delivered.

5. In a machine for grinding coiled springs, the combinationof a hopper for receiving the springs, a feeding device for receiving the springs from the hopper and 1 carrying them forward, means at opposite sides of said feedingdevice for compressing said springs longitudinally as they are fed along, and means whereby said springs are held under such compression while being ground.

6.'In a machine for grinding coiled springs, the combination of a hopper for receiving the springs, a feeding device for receiving the springs from the hopper and carrying them forward laterally,a.pair of guides at opposite sides of said feeding device, said guide having surfaces for engaging the ends of said springs as they are fed forward, said surfaces converging in the di-.

rection in which the springs are fed, whereby said springs are compressed as they are fed along, and means whereby said springs are held under compression while being ground.

7. In a machine for grinding coiled springs, the combination of a hopper for receiving the springs, a feeding device for re ceiving the springs from the hopper and carrying them forward laterally, a pair of guides at opposite sides of. said feeding device, said guides having converging surfaces for engaging the ends of said springs as they are fed forward and compressing them, and means whereby said guides can be adjusted toward and from each other to regulate the length of the springs when compressed thereby.

8. In a machine for grinding coiled springs, thecombination of a hopper for receiving the springs, a feeding device for receiving the springs from the hopper and carrying them forward laterally,-a pair of guides at opposite sides of said feeding device, said guides having surfaces for engaging the ends of said springs as they are fed forward, said surfaces converging in the direction in which the springs are fed, whereby said springs are compressed as they are fed along, means for holding the springs in compressed condition, means whereby said guides can be adjusted toward and from each other to regulate the length of the springs when compressed thereby, a pair of grinding wheels located on opposite sides of the path of said feeding device-in position to grind the ends of said springs while being fed along, and means whereby said wheels can be adjusted toward and from each other. I

9. In a machine for grinding coiled springs, the combination of a hopper for feeding the springs, a conveyer for feeding the springs forward, said conveyer comprising a plurality of elements connected with each other, and a pair of jaws carried by each element, the forward jaw of one element being adapted to cooperate with the rear jaw of the next preceding element, and

movable directly under the hopper, one of between them.

10. In a machine for grinding coiled springs, the combination of a hopper for feeding the springs, a conveyer for feeding the springs forward, said conveyer comprising a plurality of' elements connected with each other, a pair of jaws carried by each element, and movable directly under the hopper, one of the jaws of each pair being provided with a projection extending in the direction of travel thereof and bridging the space between the two jaws when open whereby when a spring is fed down between the two jaws it will be held between them, and means carried by said jaws and co operating with the hopper for preventing the feeding of the springs except when a pair of open jaws is below the hopper in position for receiving a spring.

11. In a grinding machine, the combination of a hopper for feeding articles to be ground, an endlessconveyer passing under said hopper and comprising a series of links pivotally connected together, a pair of outwardly facing jaws supported by each link whereby the forward jaw on each link cooperates with the rear jaw on the next link, each forward jaw being provided with a horn projecting therefrom for preventing articles fed betweenthe aws from being dislodged, and yielding means for forcing the rear jaw on each link toward the forward aw on the next link to the rear.

12. In a grinding machine, the combination of a hopper for feeding articles to be ground, an endless conveyer passing under said hopper and comprising a series of links pivotally connected together, a pair of outwardly oppositely facing jaws supported by each link whereby the forward jaw on each link cooperates with the rear jaw on the next link, and yielding means for forcing the rear jaw on each link toward the forward jaw on the next link to the rear.

13. In a grinding machine, the combinationwith a grinding device, an endless conveyer passing adjacent thereto and comprising a series of links pivotally connected together, a pair of outwardly facing jaws supported by each link, the forward jaw on each link coo'perating with the rear jaw on the next link to grip an article to be ground,

and yielding means for forcing the rear jaw on each link toward the forward jaw on the next linkto the rear, each forward jaw being in position to force the rear jaw on the next link forward when gripping an article between them.

.14. In a grinding machine, the combinathe next link to grip an article to be ground,

and yielding means for forcing the rear jaw on each link toward the forward jaw on the next link to the rear, each rear jaw having stops to limit its motions in both directions.

15. In a grinding machine, the combination with a grinding device of an endless conveyer for the articles to be ground comprising a series of links each link having a fixed aw on the front thereof and a movable aw on the rear, each jaw coiiperating with the adjacent jaw of the next link.

16. In a grinding machine, the combination with a grinding device, of an endless conveyer for the articles to be ground, comprising a series of links each link having a forward jaw having two forward clamping surfaces at an angle to each other, and a rear jaw having a rear convex surface.

17. In a grinding machine,-the combination of an endless conveyer comprising a series of links pivotally connected together, a pair of outwardly facing jaws supported by each link whereby the forward jaw on each link cooperates with the rear jaw on the next link, each forward jaw being provided with a horn projecting therefrom, and stationary inclined rods-at the discharge end ofthe conveyer for engaging the articles that have been ground and discharging them.

18'. In a grinding machine, thecombination of an endless conveyer comprising a series of links pivotally connected together, a pair of jaws supported by each link, and stationary inclined rods at the discharge end of the conveyer for engaging the articles that have been ground and discharging them.

19. In a machine for grinding coiled springs, the combination with means for feeding said springs forward laterally, means located at the sides .of said feeding means for compressing said, springs to a uniform length, means arranged to grip said springs while in said com-pressed condition, hold them in that condition, and feed them forward, a pair of grinding wheels in position to grind the opposite ends of said springs while held in compressed. condition,

and means whereby said springs are released said springs as they are fed along, grinding In testimony whereof I have hereunto set means on opposite sides of said feeding demy hand, in the presence of two subscribing vice, means for centering said feeding dewitnesses.

vice between the grinding means and hold- FREDERICK H. HALSTEAD; 5 ing it in proper position, and means where- Witnesses:

by said springs are held under compression ALBERT E. FAY,

while being ground. C. Fommsr WESSON. 

